1. Field of the Invention
The present invention relates to a mask strap adjuster, and more particularly to a scuba diving mask strap adjuster that is smaller.
2. Description of Related Art
Water sports are very popular. A mask is basic equipment to allow a swimmer to be able to see when underwater. Since people's heads are different sizes, swimmers need to adjust the mask's strap for a snug fit. The strap needs a mask strap adjuster to adjust the strap.
With reference to FIG. 8, a conventional mask strap adjuster comprises a base (50), a tongue (51) and two arms (52).
The base (50) has a front end, a rear end, a top side, a bottom side, a top notch (53), a bottom notch (54) and a pin. The top notch (53) and the bottom notch (54) are formed respectively in the top and bottom sides near the rear end of the base (50). The pin is mounted rotatably in the rear end of the base (50).
The tongue (51) has a proximal end, a distal end, a pawl, a top edge, a bottom edge, an inner surface, two inclined surfaces (55) and a mounting post (56). The proximal end of the tongue (51) is connected to the front end of the base (50). The pawl is formed at and protrudes in from the distal end. The inclined surfaces (55) are formed respectively on and extend out from the top and bottom edges near the distal end of the tongue (51). The mounting post (56) is formed at and protrudes from the inner surface near the proximal end of the tongue (51) and extends into the mask to attach the base (50) to the mask.
Each arm (52) has a proximal end, a distal end, an inner surface and a nub (57). The proximal ends of the arms (52) are connected respectively to the top and bottom sides of the tongue (51) near the proximal end of the tongue (51). The nub (57) is formed respectively on and extends out of each inner surface of the arms (52) near the distal end of the arm (52). The nubs (57) extend respectively into the top and bottom notches (53, 54) in the base (50) and selectively press the inclined surfaces (55) on the tongue (51).
A strap (60) is threaded around the rolling rod in the base (50) and has an outer surface and multiple triangular ribs (61). The triangular ribs (61) are formed on and protrude from the outer surface of the strap (60) and are engaged selectively by the distal end of the tongue (51).
The triangular ribs (61) on the strap (60) keep the strap (60) from loosening. To loosen the strap (60), the two arms (52) are pushed down, and the nubs (57) press the inclined surfaces (55) on the tongue (51), which forces the pawl on the tongue (51) to disengage from the triangular ribs (61) on the strap (60). The strap (60) can be pulled or released to adjust the tension on the strap (60).
When the tension of the strap (60) is adjusted, the arms (52) are released, and the pawl on the tongue (51) engages a triangular rib (61) on the strap (60) to hold the strap (60) tight.
However, the tongue (51) must be long enough to be flexible to engage the triangular ribs (61) on the strap (60). If the length of the tongue (51) is not long enough, the tongue (51) will not be strong enough to keep the strap (60) from loosening. Consequently, the base (50) and tongue (51) cannot be small.
Furthermore, the arms (52) easily break from the tongue (51). If the arms (52) break, the tension on the strap (60) cannot be released.
To overcome the shortcomings, the present invention provides a mask strap adjuster to obviate or mitigate the aforementioned problems.